Optical storage media include compact discs (CDs) and digital versatile discs (DVDs) that are commonly used to store digital data on a plastic substrate. These discs are read by optical disc drives that spin the discs while focusing a laser on the spinning disc. Changes in the reflection of the laser from the spinning disc are measured to read the data stored on the disc. Some optical drives can also write data to recordable media using a laser to change the light reflecting characteristics of photosensitive materials in the recordable media.
Optical drives are used in a number of devices including personal computers, computer servers, CD players and recorders, DVD players and recorders, and video game consoles. Optical discs are used, e.g., to store computer data, to transfer data between computers, to install software, update software, and to deliver audio and video. In order for an optical drive to read or write a disc, the disc is first loaded into the optical drive. There are a number of loading mechanisms for single disc optical drives with the two most prevalent loading types generally being tray loading, and slot loading drives.